Document Type : Original Article


University of Tehran


Mixing is one of the first and necessary steps in the industrial process of rubber production. The main purpose of mixing involves combining materials, adding energy to break the molecular bonds, and combining materials with air. Executive operation is effective in the mixing quality. The present research is on the non-isothermal simulation of mixing in a Banbury mixer. Three-dimensional numerical studies, using computational fluid dynamics, have been carried out in order to use different operational parameters. The movement of the surfaces in the calculations has been considered through the sliding mesh technique, and the fluid volume method has been used in the Eulerian approach to track the interface between the rubber phase and air. The carreau-Yasuda non-Newtonian viscosity model, along with an Arrhenius formula, has been used to determine the temperature-dependent viscosity of rubber. The results of this research show that the high viscosity of rubber becomes viscous when heated. This phenomenon is especially in the narrow area between the tip of the rotor and the wall, where there is a higher shear, and this factor affects the viscosity and flow characteristics of the rubber.


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